Apparatus for simulating the sound of a swinging bell



y 3, 1956 F. w. MULLER 2,744,583

APPARATUS FOR SIMULATING THE SOUND OF A SWINGING BELL Filed Jan. 9, 1952 MEN?" United States Patent APPARATUS FOR SHVIULATING THE SOUND OF A SWINGING BELL Friedrich Wilhelm Miiller, Hamburg-Blankenese, Germany, assignor to Hartford National Bank and Trust Company, Hartford, Conn., as trustee The present invention relates to reproducing apparatus adapted to simulate the sound originating from a source whose physical position is shifted periodically.

The so-called Doppler-effect is known to occur with relative movements between a sound source and the observer. There are periodically shifted sound sources, for example, church bells, which precisely as a result of their movement produce the peculiar swelling and decaying sound-eifects. The low displaceability and not in the last place the high outlay of the heavy bells have prompted the wish to imitate chiming for churches or the like with the use of elcctro-acoustic means without any damage to the usual sound image. For this purpose it has been suggested to use with chiming for churches or the like an electro-acoustic device for transferring stereophonic sounds by means of one or more magnetic recording devices for transfer with the use of two channels, the microphones used for recording the sound being arranged on either side of the swinging bell and at least approximately in the direction of its movement and two loudspeakers or groups of loudspeakers arranged on two opposite sides of the tower serving for reproduction.

The invention provides means for obtaining in a simpler manner stereophonic sounds giving the impression of originating from periodically shifted sound sources.

According to the invention, in such a device the loudspeaker for the reproduction of the sound is adapted to move in a manner similar to the original sound source and is connected, preferably via an amplifier, to a reproducing device, for example the scanning head of a magnetic recording device, on whose sound carrier are recorded the sounds of the original stationary sound source.

In principle, the invention is suited for the production of stereophonic sounds giving the impression of originating from sound sources shifted in some way. All that need 2 be done is move the loudspeaker for the reproduction of the sound in the same manner as the original sound source normally moves. The invention is particularly important with periodically shifted sound sources, for example with church bells or the like.

In this case the arrangement may be as shown in the figure of the accompanying drawing, in which one embodiment of the invention is shown by way of example. A loudspeaker 2 for the sound reproduction is either connected to associated sound directing surfaces or incorporated in a, say, bell-shaped sound-directing body 1, which is arranged at 3 so as to be adapted to move together with the loudspeaker. The loudspeaker is connected via a flexible lead or the like to the output of a reproduction amplifier V, whose output has supplied to it the oscillations originating from the scanning head of the magnetic recording device M. The sound carrier of the magnetic recording device M has recorded on it sounds which may have been obtained by striking a stationary church bell. If the loudspeaker 2 is moved jointly with the sound directing body 1 in the same manner as the original sound source, the usual sound image can be obtained directly.

What I claim is:

1. Apparatus for simulating the sound produced by a given swinging bell comprising a swingable electroacoustic system comprising a sound generating member and a sound directing member connected to said sound generating member, and means for applying to said sound generating member an electrical signal corresponding to the sound of said given bell when stationary.

2. Apparatus for simulating the sound produced by a given swinging bell, comprising a loudspeaker, a swingable bell-shaped sound-directing horn for housing said loudspeaker, and means for applying to said loudspeaker an electrical signal corresponding to the sound of said given bell when stationary.

References Cited in the file of this patent UNITED STATES PATENTS 1,508,432 Wier Sept. 16, 1924 1,855,149 Jones Apr. 13, 1927 1,748,225 Hoch et al. Feb. 25, 1930 2,489,653 Leslie Nov. 29, 1949 2,490,466 Olson et al Dec. 6, 1949 2,507,385 Shrader May 9, 1950 FOREIGN PATENTS 447,099 Great Britain May 12, 1936 551,364 Great Britain Feb. 18, 1943 

